Starting and stopping device for airplanes



March 10, 1931.

s. SVENSON 1,795,906

STARTING AND STOPPING DEVICE FOR AIRPLANES Filed May '7, 1928 INVENTOR.SYE/Y SYEP/JD/V ATTORNEYS.

Patented Mar. 10, 1931 svEN SVENSON, or Form 'IDU LAC, WisconsinSTARTING AND STOPPING DEVICE FOR AIRPLANES Application filed May 7,1928. Serial No. 275,845.

My invention relates to airplanes. It resides, first in a means foreifecting the take-off of the plane from its landing place, such meanscomprising a winding drum which can be operated at a high speed, and inits rotation be caused to draw upon and reel acable,the free end of thelatter being lletachably connected at a point fixed with relation to thefield, so that an initial move ment of great velocity is imparted to theplane.

The connection of the free end of the cable with its fixed point ofanchorage, is detached in the concluding stage of the initial movementof the plane, and an enlargement upon the end of the now disconnectedcable is caused to actuate devices which will disconnect the drum fromits operating means and interrupt its furthermovement of rotation.

The invention resides, second, in the provision of electro-magneticmeans for arresting the travel of the plane, when the latter 7 reachesits landing place. Such means comprises a metal plate fixed at the placeof landing. The plane is provided with a co-oper- I ating magnet whichis energized as the landing is made, by a suitable generator carried bythe plane, so that as the plane alights upon the metal plate, themagnetic force becomes eifective and acts with great power to retard andthen terminate the further movement of the plane, and quickly brings itto a state of rest, in which position it will remain until the currenttothe magnet is broken. 7

Having thus outlined the nature and purposes of my invention, I will nowdescribe the embodiment shown, and point out the novelty thereof in theappended claims.

In the accompanying drawing:

Figure 1 is a view showing in side elevation a conventional airplane atrest upon a metallic landing field, in accordance with my invention;

Fig. 2 is an enlarged View, similar to Fig. 1, with part of the body ofthe plane broken out, to show features of the mechanism;

Fig. 3 is an enlarged transverse sectional view, on the line 3-3, Fig.2, showing details of the magnet, the generator, and the controllingswitch.

Fig. 4 is a fragmentary plan view showing a portion of the metallicfield and the means by which the detachable connection of the free endof the cable with the fixed anchorage is efi'ected.

In the drawing, the numeral 10 indicates the body of an airplane of, itmay be, conventional construction. Connected to and driven from themotor shaft, is a suitable journaled counter shaft 11, having a windingdrum 12, mounted for free rotation thereon.-- A sliding clutch member18, splined upon the shaft 11, is adapted to be engaged with the drum12, and couple the latter to the shaft 11, so as to be rotatedtherewith. A clutch-actuating lever 14 is pivoted upon a bracket 15.Extending rearwardly, and in position to be operated by the pilot of theplane, is a hand leverl6, connected to the clutch-actuating lever 14, inthe line of the pivotal point of the latter. By this means, the drum 12may be clutched to the shaft 11, and unclutched therefrom.

Extending'forwardly of the pivot of the clutch-actuating lever 14, andconnected thereto, is a radial arm 17 to the free end of which isconnected the upper end of a link 18, the lower end of which is providedwith a constricted angular eye piece 19, for a purpose whichwill laterbe described.

A cable 20 of considerable length is attached at one end tothe drum 12,and normally wound thereon, the said cable passing through the eye piece19 of the link 18, and having upon its farther free end, a button orknot, or other enlargement, 21, of a diameter exceeding that of the eye19, the constriction of'whichforbids the passage of the said enlargementtherethrough.

WVith the airplane at rest, the cable is unwound from vthe reel, andextended to the far edge of the field. At this place, a post 22, with anotch or upwardly opening fork is firmly fixed. The end of the cable islaid in the notch with the enlargement of the cable resting against theouter side of the post.

. When the motor of the airplane is started,

the clutch member 13 isthrown into engagement With the drum 12, bylifting the hand lever 16, and the plane moves forward with the windingup of the cable. As the speed of the motor is increased, the speed ofthe airplane is accelerated. The plane will rise, and the enlargement 21at the free end of the cable will lee-removed from .the notch orupwardly openingfork of the post '22.. Thereafter, the said enlargementof the cable will reach the constricted eye piece 19 of the link 18,and, through the instrumentality of said link, will cause the radial arm17 to be lifted, the clutch-actuating lever 14 to be raised, and thesliding clutch member 13 tobe withdrawn from engagement with the windingdrum 12, to'thus free the said drum from ro-' tating connection with thecounter shaft 11. Thereupon, the winding drum will assume a stationaryposition, aswill be obvious, and the airplane will proceed withoutinterruption.

To effect the stopping of the airplane and check its movement uponlanding, I form a landing area by arranging a fiat metal surface orsheet 23, secured :inimmovable position, at the place where the desiredlanding is to be-ma-de. Upon the airplane, and preferably at itsunderside near the rear end,I arrange a magnet "24, thepoles 25 and 26of which project downwardly to the ground line ofthe machine. The polesare arranged at the opopsite ends of the core 27, which latter may havea slight rotatory motion in the coil '28, so as to adapt the shoe facesof the poles of the magnet 24, to inequalities of the landing sheet, andpermit a perfect contact to be made. A stay wire 29, attached forwardlyto the-body of the airplane, and rearwardly to the poles of the magnet,serves to limit the rotating motion of the poles, and hold them in asubstantially horizontal plane.

To energize the magnet 24, I equip the airplane with a generator 30 ofsuitable capacity, a battery being illustrated as a generator.Connections 31 and 32 lead from the generator to the magnet. In thecircuit 32, I insert a controlling switch 33, and a rheostat 34, bymeans of which the power of the magnet may be regulatedby the pilot.

As the plane approaches the landing sheet, the switch is thrown on, andthe magnet energized by the current passing from the gen erator. Themagnet thus attracts the fixed metal sheet 23, and the power thereofexerts a pressure which acts as a drag-upon the airplane, and retardsits further movement. The magnetic attraction may be increased throughthe rheostat, until 'the plane is brought to a state of rest. Reversalof'the switch will break the connection, and leave the plane freeforanother flight.

It is desirable, insome instances, that the metal plate 23, be arrangedat an angle from the horizontal, so as to present an added resistance tothe-movement of the plane, up

wardly of the inclined surface of the landing plate.

Having thus described my invention, what I claim and desire to secure byLetters Patent of the United States, is:

1. An airplane provided with a magnet at its ground line, the saidmagnet comprising two-poles and a coil for energizing-the magnet, thepoles being journaled so as to have a rotative movement with relation tothe coil, a generator for supplying current to the coil, and meanscontrolled by the pilot of the plane for energizing the coil to causethe magnet to function as a stop for the plane when landing.

2. An airplane provided with a magnet at its ground line, thesaid magnetcomprising a coil and poles having a rotative movement with relationthereto, and means for energizing the magnet to cause it to function-asa stop for the plane when landing.

In testimony whereof, I have signed my name at Milwaukee, this 21st dayof April,

SVEN SVENSON.

